How do you go about becoming part of the stock photography market?

just take pics for stock
after a few years you will have a library you can submit to pic agencies if you want, but it is better to market them yourself if possible

Have the right equipment. You need to shoot with a pro camera and good lenses. Image file quality is important. You also need to know how to prep the images in photoshop and embedded meta data (key wording)

Do your research and see what the market needs when it comes to images. Keeping track of trends is also very important. What is hot right now.

Create a library of fantastic images. Just good is not good enough. Most stock images will never sell. Be prepared to not see a return on them.

What ever you do take the time and register your copyright of all your images before you go to an agency. They are sharks and you need that protection. It is fast to do and if you submit a lot of images not that expensive.

Lastly after you have created some quality images you can either go to the big two Getty and Corbis or smaller agencies. It is getting harder and hart er to get into one of those. They are really more interested to own all the copyright and not share income with the artist.

Other options:
Your own database website you do your own sells. A software like fotobiz/fotoquote will help you with pricing.

http://www.MIRA.com (photographer co-op)
www.photoshelter.com
www.digitalrailroad.com

Only you know what is best for you.

Do you really want to go into stock photography?

Do you think it is good for the Photography industry as a whole?

Wouldn't you prefer to work for commissions for a decent fee instead of flooding the market with generic images?

By purchasing some.